If using external png need to link vtkpython with it.
If using external png need to link vtkpython with it.

Change-Id: I8ea03dd6bcad307ac52ca9d64fe67a20c8a8e5cd

SimVascular/VTK,biddisco/VTK,sankhesh/VTK,gram526/VTK,gram526/VTK,jmerkow/VTK,msmolens/VTK,sumedhasingla/VTK,sumedhasingla/VTK,demarle/VTK,msmolens/VTK,gram526/VTK,keithroe/vtkoptix,msmolens/VTK,collects/VTK,gram526/VTK,keithroe/vtkoptix,demarle/VTK,collects/VTK,keithroe/vtkoptix,hendradarwin/VTK,johnkit/vtk-dev,ashray/VTK-EVM,sankhesh/VTK,candy7393/VTK,mspark93/VTK,candy7393/VTK,msmolens/VTK,sumedhasingla/VTK,biddisco/VTK,sankhesh/VTK,sankhesh/VTK,aashish24/VTK-old,spthaolt/VTK,sumedhasingla/VTK,johnkit/vtk-dev,demarle/VTK,msmolens/VTK,candy7393/VTK,spthaolt/VTK,mspark93/VTK,jmerkow/VTK,mspark93/VTK,mspark93/VTK,SimVascular/VTK,demarle/VTK,candy7393/VTK,ashray/VTK-EVM,keithroe/vtkoptix,mspark93/VTK,msmolens/VTK,ashray/VTK-EVM,SimVascular/VTK,candy7393/VTK,keithroe/vtkoptix,candy7393/VTK,collects/VTK,spthaolt/VTK,SimVascular/VTK,johnkit/vtk-dev,msmolens/VTK,cjh1/VTK,ashray/VTK-EVM,mspark93/VTK,sankhesh/VTK,cjh1/VTK,biddisco/VTK,demarle/VTK,ashray/VTK-EVM,candy7393/VTK,biddisco/VTK,gram526/VTK,sumedhasingla/VTK,aashish24/VTK-old,SimVascular/VTK,hendradarwin/VTK,mspark93/VTK,SimVascular/VTK,cjh1/VTK,biddisco/VTK,keithroe/vtkoptix,berendkleinhaneveld/VTK,sankhesh/VTK,aashish24/VTK-old,jmerkow/VTK,spthaolt/VTK,jmerkow/VTK,hendradarwin/VTK,ashray/VTK-EVM,msmolens/VTK,cjh1/VTK,collects/VTK,johnkit/vtk-dev,johnkit/vtk-dev,biddisco/VTK,cjh1/VTK,SimVascular/VTK,spthaolt/VTK,aashish24/VTK-old,jmerkow/VTK,sumedhasingla/VTK,berendkleinhaneveld/VTK,spthaolt/VTK,demarle/VTK,sankhesh/VTK,demarle/VTK,gram526/VTK,gram526/VTK,spthaolt/VTK,cjh1/VTK,ashray/VTK-EVM,hendradarwin/VTK,sankhesh/VTK,aashish24/VTK-old,jmerkow/VTK,gram526/VTK,jmerkow/VTK,hendradarwin/VTK,berendkleinhaneveld/VTK,keithroe/vtkoptix,hendradarwin/VTK,biddisco/VTK,hendradarwin/VTK,mspark93/VTK,aashish24/VTK-old,berendkleinhaneveld/VTK,johnkit/vtk-dev,berendkleinhaneveld/VTK,berendkleinhaneveld/VTK,johnkit/vtk-dev,demarle/VTK,SimVascular/VTK,candy7393/VTK,jmerkow/VTK,sumedhasingla/VTK,berendkleinhaneveld/VTK,collects/VTK,keithroe/vtkoptix,sumedhasingla/VTK,ashray/VTK-EVM,collects/VTK